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view mercurial/repair.py @ 48687:f8f2ecdde4b5
branchmap: skip obsolete revisions while computing heads
It's time to make this part of core Mercurial obsolescence-aware.
Not considering obsolete revisions when computing heads is clearly what
Mercurial should do. But there are a couple of small issues:
- Let's say tip of the repo is obsolete. There are two ways of finding tiprev
for branchcache (both are in use): looking at input data for update() and
looking at computed heads after update(). Previously, repo tip would be
tiprev of the branchcache. With this patch, an obsolete revision can no
longer be tiprev. And depending on what way we use for finding tiprev (input
data vs computed heads) we'll get a different result. This is relevant when
recomputing cache key from cache contents, and may lead to updating cache for
obsolete revisions multiple times (not from scratch, because it still would
be considered valid for a subset of revisions in the repo).
- If all commits on a branch are obsolete, the branchcache will include that
branch, but the list of heads will be empty (that's why there's now `if not
heads` when recomputing tiprev/tipnode from cache contents). Having an entry
for every branch is currently required for notify extension (and
test-notify.t to pass), because notify doesn't handle revsets in its
subscription config very well and will throw an error if e.g. a branch
doesn't exist.
- Cloning static HTTP repos may try to stat() a non-existent obsstore file. The
issue is that we now care about obsolescence during clone, but statichttpvfs
doesn't implement a stat method, so a regular vfs.stat() is used, and it
assumes that file is local and calls os.stat(). During a clone, we're trying
to stat() .hg/store/obsstore, but in static HTTP case we provide a literal
URL to the obsstore file on the remote as if it were a local file path. On
windows it actually results in a failure in test-static-http.t.
The first issue is going to be addressed in a series dedicated to making sure
branchcache is properly and timely written on disk (it wasn't perfect even
before this patch, but there aren't enough tests to demonstrate that). The
second issue will be addressed in a future patch for notify extension that will
make it not raise an exception if a branch doesn't exist. And the third one was
partially addressed in the previous patch in this series and will be properly
fixed in a future patch when this series is accepted.
filteredhash() grows a keyword argument to make sure that branchcache is also
invalidated when there are new obsolete revisions in its repo view. This way
the on-disk cache format is unchanged and compatible between versions (although
it will obviously be recomputed when switching versions before/after this patch
and the repo has obsolete revisions).
There's one test that uses plain `hg up` without arguments while updated to a
pruned commit. To make this test pass, simply return current working directory
parent. Later in this series this code will be replaced by what prune command
does: updating to the closest non-obsolete ancestor.
Test changes:
test-branch-change.t: update branch head and cache update message. The head of
default listed in hg heads is changed because revision 2 was rewritten as 7,
and 1 is the closest ancestor on the same branch, so it's the head of default
now.
The cache invalidation message appears now because of the cache hash change,
since we're now accounting for obsolete revisions. Here's some context:
"served.hidden" repo filter means everything is visible (no filtered
revisions), so before this series branch2-served.hidden file would not contain
any cache hash, only revnum and node. Now it also has a hash when there are
obsolete changesets in the repo. The command that the message appears for is
changing branch of 5 and 6, which are now obsolete, so the cache hash changes.
In general, when cache is simply out-of-date, it can be updated using the old
version as a base. But if cache hash differs, then the cache for that
particular repo filter is recomputed (at least with the current
implementation). This is what happens here.
test-obsmarker-template.t: the pull reports 2 heads changed, but after that the
repo correctly sees only 1. The new message could be better, but it's still an
improvement over the previous one where hg pull suggested merging with an
obsolete revision.
test-obsolete.t: we can see these revisions in hg log --hidden, but they
shouldn't be considered heads even with --hidden.
test-rebase-obsolete{,2}.t: there were new heads created previously after
making new orphan changesets, but they weren't detected. Now we are properly
detecting and reporting them.
test-rebase-obsolete4.t: there's only one head now because the other head is
pruned and was falsely reported before.
test-static-http.t: add obsstore to the list of requested files. This file
doesn't exist on the remotes, but clients want it anyway (they get 404). This
is fine, because there are other nonexistent files that clients request, like
.hg/bookmarks or .hg/cache/tags2-served.
Differential Revision: https://phab.mercurial-scm.org/D12097
author | Anton Shestakov <av6@dwimlabs.net> |
---|---|
date | Fri, 07 Jan 2022 11:53:23 +0300 |
parents | 2174f54aab18 |
children | 6000f5b25c9b |
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# repair.py - functions for repository repair for mercurial # # Copyright 2005, 2006 Chris Mason <mason@suse.com> # Copyright 2007 Olivia Mackall # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import errno from .i18n import _ from .node import ( hex, short, ) from . import ( bundle2, changegroup, discovery, error, exchange, obsolete, obsutil, pathutil, phases, pycompat, requirements, scmutil, util, ) from .utils import ( hashutil, stringutil, urlutil, ) def backupbundle( repo, bases, heads, node, suffix, compress=True, obsolescence=True ): """create a bundle with the specified revisions as a backup""" backupdir = b"strip-backup" vfs = repo.vfs if not vfs.isdir(backupdir): vfs.mkdir(backupdir) # Include a hash of all the nodes in the filename for uniqueness allcommits = repo.set(b'%ln::%ln', bases, heads) allhashes = sorted(c.hex() for c in allcommits) totalhash = hashutil.sha1(b''.join(allhashes)).digest() name = b"%s/%s-%s-%s.hg" % ( backupdir, short(node), hex(totalhash[:4]), suffix, ) cgversion = changegroup.localversion(repo) comp = None if cgversion != b'01': bundletype = b"HG20" if compress: comp = b'BZ' elif compress: bundletype = b"HG10BZ" else: bundletype = b"HG10UN" outgoing = discovery.outgoing(repo, missingroots=bases, ancestorsof=heads) contentopts = { b'cg.version': cgversion, b'obsolescence': obsolescence, b'phases': True, } return bundle2.writenewbundle( repo.ui, repo, b'strip', name, bundletype, outgoing, contentopts, vfs, compression=comp, ) def _collectfiles(repo, striprev): """find out the filelogs affected by the strip""" files = set() for x in pycompat.xrange(striprev, len(repo)): files.update(repo[x].files()) return sorted(files) def _collectrevlog(revlog, striprev): _, brokenset = revlog.getstrippoint(striprev) return [revlog.linkrev(r) for r in brokenset] def _collectbrokencsets(repo, files, striprev): """return the changesets which will be broken by the truncation""" s = set() for revlog in manifestrevlogs(repo): s.update(_collectrevlog(revlog, striprev)) for fname in files: s.update(_collectrevlog(repo.file(fname), striprev)) return s def strip(ui, repo, nodelist, backup=True, topic=b'backup'): # This function requires the caller to lock the repo, but it operates # within a transaction of its own, and thus requires there to be no current # transaction when it is called. if repo.currenttransaction() is not None: raise error.ProgrammingError(b'cannot strip from inside a transaction') # Simple way to maintain backwards compatibility for this # argument. if backup in [b'none', b'strip']: backup = False repo = repo.unfiltered() repo.destroying() vfs = repo.vfs # load bookmark before changelog to avoid side effect from outdated # changelog (see repo._refreshchangelog) repo._bookmarks cl = repo.changelog # TODO handle undo of merge sets if isinstance(nodelist, bytes): nodelist = [nodelist] striplist = [cl.rev(node) for node in nodelist] striprev = min(striplist) files = _collectfiles(repo, striprev) saverevs = _collectbrokencsets(repo, files, striprev) # Some revisions with rev > striprev may not be descendants of striprev. # We have to find these revisions and put them in a bundle, so that # we can restore them after the truncations. # To create the bundle we use repo.changegroupsubset which requires # the list of heads and bases of the set of interesting revisions. # (head = revision in the set that has no descendant in the set; # base = revision in the set that has no ancestor in the set) tostrip = set(striplist) saveheads = set(saverevs) for r in cl.revs(start=striprev + 1): if any(p in tostrip for p in cl.parentrevs(r)): tostrip.add(r) if r not in tostrip: saverevs.add(r) saveheads.difference_update(cl.parentrevs(r)) saveheads.add(r) saveheads = [cl.node(r) for r in saveheads] # compute base nodes if saverevs: descendants = set(cl.descendants(saverevs)) saverevs.difference_update(descendants) savebases = [cl.node(r) for r in saverevs] stripbases = [cl.node(r) for r in tostrip] stripobsidx = obsmarkers = () if repo.ui.configbool(b'devel', b'strip-obsmarkers'): obsmarkers = obsutil.exclusivemarkers(repo, stripbases) if obsmarkers: stripobsidx = [ i for i, m in enumerate(repo.obsstore) if m in obsmarkers ] newbmtarget, updatebm = _bookmarkmovements(repo, tostrip) backupfile = None node = nodelist[-1] if backup: backupfile = _createstripbackup(repo, stripbases, node, topic) # create a changegroup for all the branches we need to keep tmpbundlefile = None if saveheads: # do not compress temporary bundle if we remove it from disk later # # We do not include obsolescence, it might re-introduce prune markers # we are trying to strip. This is harmless since the stripped markers # are already backed up and we did not touched the markers for the # saved changesets. tmpbundlefile = backupbundle( repo, savebases, saveheads, node, b'temp', compress=False, obsolescence=False, ) with ui.uninterruptible(): try: with repo.transaction(b"strip") as tr: # TODO this code violates the interface abstraction of the # transaction and makes assumptions that file storage is # using append-only files. We'll need some kind of storage # API to handle stripping for us. oldfiles = set(tr._offsetmap.keys()) oldfiles.update(tr._newfiles) tr.startgroup() cl.strip(striprev, tr) stripmanifest(repo, striprev, tr, files) for fn in files: repo.file(fn).strip(striprev, tr) tr.endgroup() entries = tr.readjournal() for file, troffset in entries: if file in oldfiles: continue with repo.svfs(file, b'a', checkambig=True) as fp: fp.truncate(troffset) if troffset == 0: repo.store.markremoved(file) deleteobsmarkers(repo.obsstore, stripobsidx) del repo.obsstore repo.invalidatevolatilesets() repo._phasecache.filterunknown(repo) if tmpbundlefile: ui.note(_(b"adding branch\n")) f = vfs.open(tmpbundlefile, b"rb") gen = exchange.readbundle(ui, f, tmpbundlefile, vfs) # silence internal shuffling chatter maybe_silent = ( repo.ui.silent() if not repo.ui.verbose else util.nullcontextmanager() ) with maybe_silent: tmpbundleurl = b'bundle:' + vfs.join(tmpbundlefile) txnname = b'strip' if not isinstance(gen, bundle2.unbundle20): txnname = b"strip\n%s" % urlutil.hidepassword( tmpbundleurl ) with repo.transaction(txnname) as tr: bundle2.applybundle( repo, gen, tr, source=b'strip', url=tmpbundleurl ) f.close() with repo.transaction(b'repair') as tr: bmchanges = [(m, repo[newbmtarget].node()) for m in updatebm] repo._bookmarks.applychanges(repo, tr, bmchanges) # remove undo files for undovfs, undofile in repo.undofiles(): try: undovfs.unlink(undofile) except OSError as e: if e.errno != errno.ENOENT: ui.warn( _(b'error removing %s: %s\n') % ( undovfs.join(undofile), stringutil.forcebytestr(e), ) ) except: # re-raises if backupfile: ui.warn( _(b"strip failed, backup bundle stored in '%s'\n") % vfs.join(backupfile) ) if tmpbundlefile: ui.warn( _(b"strip failed, unrecovered changes stored in '%s'\n") % vfs.join(tmpbundlefile) ) ui.warn( _( b"(fix the problem, then recover the changesets with " b"\"hg unbundle '%s'\")\n" ) % vfs.join(tmpbundlefile) ) raise else: if tmpbundlefile: # Remove temporary bundle only if there were no exceptions vfs.unlink(tmpbundlefile) repo.destroyed() # return the backup file path (or None if 'backup' was False) so # extensions can use it return backupfile def softstrip(ui, repo, nodelist, backup=True, topic=b'backup'): """perform a "soft" strip using the archived phase""" tostrip = [c.node() for c in repo.set(b'sort(%ln::)', nodelist)] if not tostrip: return None backupfile = None if backup: node = tostrip[0] backupfile = _createstripbackup(repo, tostrip, node, topic) newbmtarget, updatebm = _bookmarkmovements(repo, tostrip) with repo.transaction(b'strip') as tr: phases.retractboundary(repo, tr, phases.archived, tostrip) bmchanges = [(m, repo[newbmtarget].node()) for m in updatebm] repo._bookmarks.applychanges(repo, tr, bmchanges) return backupfile def _bookmarkmovements(repo, tostrip): # compute necessary bookmark movement bm = repo._bookmarks updatebm = [] for m in bm: rev = repo[bm[m]].rev() if rev in tostrip: updatebm.append(m) newbmtarget = None # If we need to move bookmarks, compute bookmark # targets. Otherwise we can skip doing this logic. if updatebm: # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), # but is much faster newbmtarget = repo.revs(b'max(parents(%ld) - (%ld))', tostrip, tostrip) if newbmtarget: newbmtarget = repo[newbmtarget.first()].node() else: newbmtarget = b'.' return newbmtarget, updatebm def _createstripbackup(repo, stripbases, node, topic): # backup the changeset we are about to strip vfs = repo.vfs cl = repo.changelog backupfile = backupbundle(repo, stripbases, cl.heads(), node, topic) repo.ui.status(_(b"saved backup bundle to %s\n") % vfs.join(backupfile)) repo.ui.log( b"backupbundle", b"saved backup bundle to %s\n", vfs.join(backupfile) ) return backupfile def safestriproots(ui, repo, nodes): """return list of roots of nodes where descendants are covered by nodes""" torev = repo.unfiltered().changelog.rev revs = {torev(n) for n in nodes} # tostrip = wanted - unsafe = wanted - ancestors(orphaned) # orphaned = affected - wanted # affected = descendants(roots(wanted)) # wanted = revs revset = b'%ld - ( ::( (roots(%ld):: and not _phase(%s)) -%ld) )' tostrip = set(repo.revs(revset, revs, revs, phases.internal, revs)) notstrip = revs - tostrip if notstrip: nodestr = b', '.join(sorted(short(repo[n].node()) for n in notstrip)) ui.warn( _(b'warning: orphaned descendants detected, not stripping %s\n') % nodestr ) return [c.node() for c in repo.set(b'roots(%ld)', tostrip)] class stripcallback(object): """used as a transaction postclose callback""" def __init__(self, ui, repo, backup, topic): self.ui = ui self.repo = repo self.backup = backup self.topic = topic or b'backup' self.nodelist = [] def addnodes(self, nodes): self.nodelist.extend(nodes) def __call__(self, tr): roots = safestriproots(self.ui, self.repo, self.nodelist) if roots: strip(self.ui, self.repo, roots, self.backup, self.topic) def delayedstrip(ui, repo, nodelist, topic=None, backup=True): """like strip, but works inside transaction and won't strip irreverent revs nodelist must explicitly contain all descendants. Otherwise a warning will be printed that some nodes are not stripped. Will do a backup if `backup` is True. The last non-None "topic" will be used as the backup topic name. The default backup topic name is "backup". """ tr = repo.currenttransaction() if not tr: nodes = safestriproots(ui, repo, nodelist) return strip(ui, repo, nodes, backup=backup, topic=topic) # transaction postclose callbacks are called in alphabet order. # use '\xff' as prefix so we are likely to be called last. callback = tr.getpostclose(b'\xffstrip') if callback is None: callback = stripcallback(ui, repo, backup=backup, topic=topic) tr.addpostclose(b'\xffstrip', callback) if topic: callback.topic = topic callback.addnodes(nodelist) def stripmanifest(repo, striprev, tr, files): for revlog in manifestrevlogs(repo): revlog.strip(striprev, tr) def manifestrevlogs(repo): yield repo.manifestlog.getstorage(b'') if scmutil.istreemanifest(repo): # This logic is safe if treemanifest isn't enabled, but also # pointless, so we skip it if treemanifest isn't enabled. for t, unencoded, size in repo.store.datafiles(): if unencoded.startswith(b'meta/') and unencoded.endswith( b'00manifest.i' ): dir = unencoded[5:-12] yield repo.manifestlog.getstorage(dir) def rebuildfncache(ui, repo, only_data=False): """Rebuilds the fncache file from repo history. Missing entries will be added. Extra entries will be removed. """ repo = repo.unfiltered() if requirements.FNCACHE_REQUIREMENT not in repo.requirements: ui.warn( _( b'(not rebuilding fncache because repository does not ' b'support fncache)\n' ) ) return with repo.lock(): fnc = repo.store.fncache fnc.ensureloaded(warn=ui.warn) oldentries = set(fnc.entries) newentries = set() seenfiles = set() if only_data: # Trust the listing of .i from the fncache, but not the .d. This is # much faster, because we only need to stat every possible .d files, # instead of reading the full changelog for f in fnc: if f[:5] == b'data/' and f[-2:] == b'.i': seenfiles.add(f[5:-2]) newentries.add(f) dataf = f[:-2] + b'.d' if repo.store._exists(dataf): newentries.add(dataf) else: progress = ui.makeprogress( _(b'rebuilding'), unit=_(b'changesets'), total=len(repo) ) for rev in repo: progress.update(rev) ctx = repo[rev] for f in ctx.files(): # This is to minimize I/O. if f in seenfiles: continue seenfiles.add(f) i = b'data/%s.i' % f d = b'data/%s.d' % f if repo.store._exists(i): newentries.add(i) if repo.store._exists(d): newentries.add(d) progress.complete() if requirements.TREEMANIFEST_REQUIREMENT in repo.requirements: # This logic is safe if treemanifest isn't enabled, but also # pointless, so we skip it if treemanifest isn't enabled. for dir in pathutil.dirs(seenfiles): i = b'meta/%s/00manifest.i' % dir d = b'meta/%s/00manifest.d' % dir if repo.store._exists(i): newentries.add(i) if repo.store._exists(d): newentries.add(d) addcount = len(newentries - oldentries) removecount = len(oldentries - newentries) for p in sorted(oldentries - newentries): ui.write(_(b'removing %s\n') % p) for p in sorted(newentries - oldentries): ui.write(_(b'adding %s\n') % p) if addcount or removecount: ui.write( _(b'%d items added, %d removed from fncache\n') % (addcount, removecount) ) fnc.entries = newentries fnc._dirty = True with repo.transaction(b'fncache') as tr: fnc.write(tr) else: ui.write(_(b'fncache already up to date\n')) def deleteobsmarkers(obsstore, indices): """Delete some obsmarkers from obsstore and return how many were deleted 'indices' is a list of ints which are the indices of the markers to be deleted. Every invocation of this function completely rewrites the obsstore file, skipping the markers we want to be removed. The new temporary file is created, remaining markers are written there and on .close() this file gets atomically renamed to obsstore, thus guaranteeing consistency.""" if not indices: # we don't want to rewrite the obsstore with the same content return left = [] current = obsstore._all n = 0 for i, m in enumerate(current): if i in indices: n += 1 continue left.append(m) newobsstorefile = obsstore.svfs(b'obsstore', b'w', atomictemp=True) for bytes in obsolete.encodemarkers(left, True, obsstore._version): newobsstorefile.write(bytes) newobsstorefile.close() return n